Network Node and Method Performed Therein for Controlling Transmission

3. The method according to claim 2, wherein the call establishment of the terminating request towards the UE does not explicitly wait for a re-registering response from the core IMS node.

4. The method according to claim 2, wherein the call establishment of the terminating request towards the UE does not explicitly wait for a response for the re-registering of the UE to establish a call.

6. The method according to claim 1, wherein the registration information of the UE includes one or more of the following: push notification parameter, registration session information, contact information for the UE, or any combination thereof.

9. The network node according to claim 8, wherein the call establishment of the terminating request towards the UE does not explicitly wait for a re-register response from the core IMS node.

10. The network node according to claim 8, wherein the call establishment of the terminating request towards the UE does not explicitly wait for a response for the re-registering to establish a call.

11. The network node according to claim 7, wherein the network node is further configured to store the registration information upon registration of the UE.

12. The network node according to claim 7, wherein the registration information of the UE includes one or more of the following: push notification parameter, registration session information, contact information for the UE, or any combination thereof.

15. The non-transitory computer-readable storage medium according to claim 14, wherein the call establishment of the terminating request towards the UE does not explicitly wait for a re-registering response from the core IMS node.

16. The non-transitory computer-readable storage medium according to claim 14, wherein the call establishment of the terminating request towards the UE does not explicitly wait for a response for the re-registering of the UE to establish a call.

18. The non-transitory computer-readable storage medium according to claim 13, wherein the registration information of the UE includes one or more of the following: push notification parameter, registration session information, contact information for the UE, or any combination thereof.